👉 In physics, a "fuseless" system refers to a device that can be used in an unimpeded manner without any external power supply. This includes both electrical and mechanical devices. A fuse is a type of circuit breaker or switch which has a mechanism to stop or interrupt the flow of electricity when it's not needed. A fuse is designed to prevent the failure of the circuit, but does not require any external power source. In contrast, an uncontrolled power supply can cause damage or malfunction